A production halt at Newmont Mining Corp.'s (NEM) Indonesian operations may reduce this year's output by a maximum of about 10%, an official at the Department of Energy and Mineral Resources said Monday.

Witoro Soelarno, a director for minerals and geothermal at the ministry, told reporters that PT Newmont Nusa Tenggara may have to stop its operations at the Batu Hijau copper and gold mine for as long as three months as it investigates a landslide that occurred at the area earlier this month.

However, "if there is a fall in production, it will not be more than 10%," he said.

PTNNT, as the unit is known, has previously said it is continuing to process ore from stocks at Batu Hijau during the halt in mining operations.

Soelarno said Newmont has enough stockpiles of ore to last four months.

A spokesman at Newmont Indonesia said Monday: "We are still in the process of evaluating the effect on PTNNT's production for 2009. We will know the effect once the evaluation team has fully evaluated the situation in the field."

He didn't provide further details.

-By Deden Sudrajat, contributing to Dow Jones Newswires; 62 21 3983 1277; Reuben.Carder@dowjones.com